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Human immunodeficiency virus (HIV) infection is associated with subclinical cardiomyopathy, diastolic dysfunction, and increased risk of cardiovascular death. However, the relationship between left atrial (LA) mechanics and left ventricular (LV) diastolic function has not been evaluated in people living with HIV (PLWH) relative to HIV-uninfected (HIV-) controls. This is a multicenter, cross-sectional cohort analysis using the HIV Cardiovascular Disease substudy of the Veterans Aging Cohort Study database, which aimed to examine a cohort of PLWH and HIV- veterans without known cardiovascular disease. A total of 277 subjects (180 PLWH, 97 HIV-) with echocardiograms were identified. LV and LA phasic strain were derived and diastolic function was evaluated. Relationship between LA strain, LV strain, and the degree of diastolic dysfunction were assessed using analysis of variance and ordinal logistic regression with propensity weighting. In the PLWH cohort, 91.7% were on antiretroviral therapy and 86.1% had HIV viral loads500 copies/ml. The mean (± SD) duration of infection was 9.7 ± 4.9 years. Relative to HIV- veterans, PLWH did not differ in LA mechanics and proportion of diastolic dysfunction (p = 0.31). Using logistic regression with propensity weighting, we found no association between HIV status and degree of diastolic dysfunction. In both cohorts, LA reservoir strain and LA conduit strain were inversely and independently associated with the degree of diastolic dysfunction. Compared with HIV- veterans, PLWH who are primarily virally suppressed and antiretroviral-treated did not differ in LA strain or LV diastolic dysfunction. If confirmed in other cohorts, HIV viral suppression may curtail adverse alterations in cardiac structure and function.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) monoclonal antibodies (mAbs) are among the treatments recommended for high-risk ambulatory persons with coronavirus 2019 (COVID-19). Here, we study viral culture dynamics post-treatment in a subset of participants receiving the mAb bamlanivimab in the ACTIV-2 trial (ClinicalTrials.gov: NCT04518410). Viral load by qPCR and viral culture are performed from anterior nasal swabs collected on study days 0 (day of treatment), 1, 2, 3, and 7. Treatment with mAbs results in rapid clearance of culturable virus. One day after treatment, 0 of 28 (0%) participants receiving mAbs and 16 of 39 (41%) receiving placebo still have culturable virus (p 0.0001). Recrudescence of culturable virus is detected in three participants with emerging mAb resistance and viral RNA rebound. While further studies are necessary to fully define the relationship between shed culturable virus and transmission, these results raise the possibility that mAbs may offer immediate (household) and public-health benefits by reducing onward transmission.

Measuring the in vitro replication capacity of viruses is an important tool for assessing the effects of selective pressure of immune responses and drug therapy. Measuring hepatitis C virus (HCV) replication capacity utilizing primarily sub-genomic reporter constructs is limited. To overcome some of these limitations a quantitative reverse transcriptase PCR (RT-qPCR) was designed to measure simultaneously the growth rate of 2 whole genome HCV variants under identical culture conditions. The assay demonstrates 100% specificity of detection of each variant and a linear detection range from 200 to 2×10(8) copies. The system was validated using a panel of HCV mutants, including the NS3 protease inhibitor drug resistance mutants R155K and T54A. The creation of a unique sequence tag results in highly sensitive and specific discrimination of parental JFH-FNX and modified clones using distinct probes in a RT-qPCR allowing for comparison of the effect of drug resistance or immune escape mutations on HCV replication. This system has advantages over existing methods both by permitting direct comparison of the replication capacity of fully replication-competent HCV mutants under identical culture conditions and by measuring effects on replication capacity due to mutations affecting all stages of the viral life cycle including entry and egress.